package org.bouncycastle.asn1.x509;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERBitString;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERSequence;

public class AttributeCertificate extends ASN1Encodable {
    AttributeCertificateInfo acinfo;
    AlgorithmIdentifier signatureAlgorithm;
    DERBitString signatureValue;

    /**
     * @param obj
     * @return an AttributeCertificate object
     */
    public static AttributeCertificate getInstance(Object obj) {
        if (obj instanceof AttributeCertificate) {
            return (AttributeCertificate) obj;
        } else if (obj instanceof ASN1Sequence) {
            return new AttributeCertificate((ASN1Sequence) obj);
        }

        throw new IllegalArgumentException("unknown object in factory");
    }

    public AttributeCertificate(AttributeCertificateInfo acinfo, AlgorithmIdentifier signatureAlgorithm, DERBitString signatureValue) {
        this.acinfo = acinfo;
        this.signatureAlgorithm = signatureAlgorithm;
        this.signatureValue = signatureValue;
    }

    public AttributeCertificate(ASN1Sequence seq) {
        if (seq.size() != 3) {
            throw new IllegalArgumentException("Bad sequence size: " + seq.size());
        }

        this.acinfo = AttributeCertificateInfo.getInstance(seq.getObjectAt(0));
        this.signatureAlgorithm = AlgorithmIdentifier.getInstance(seq.getObjectAt(1));
        this.signatureValue = DERBitString.getInstance(seq.getObjectAt(2));
    }

    public AttributeCertificateInfo getAcinfo() {
        return acinfo;
    }

    public AlgorithmIdentifier getSignatureAlgorithm() {
        return signatureAlgorithm;
    }

    public DERBitString getSignatureValue() {
        return signatureValue;
    }

    /**
     * Produce an object suitable for an ASN1OutputStream.
     * 
     * <pre>
     *  AttributeCertificate ::= SEQUENCE {
     *       acinfo               AttributeCertificateInfo,
     *       signatureAlgorithm   AlgorithmIdentifier,
     *       signatureValue       BIT STRING
     *  }
     * </pre>
     */
    public DERObject toASN1Object() {
        ASN1EncodableVector v = new ASN1EncodableVector();

        v.add(acinfo);
        v.add(signatureAlgorithm);
        v.add(signatureValue);

        return new DERSequence(v);
    }
}
